env GOARCH=amd64
env GOAMD64=v3
go list -f '{{context.ToolTags}}'
stdout 'amd64.v1 amd64.v2 amd64.v3'

env GOARCH=arm
env GOARM=6
go list -f '{{context.ToolTags}}'
stdout 'arm.5 arm.6'

env GOARCH=mips
env GOMIPS=hardfloat
go list -f '{{context.ToolTags}}'
stdout 'mips.hardfloat'

env GOARCH=mips64
env GOMIPS=hardfloat
go list -f '{{context.ToolTags}}'
stdout 'mips64.hardfloat'

env GOARCH=ppc64

		GOOS:          c.GOOS,
		GOROOT:        c.GOROOT,
		GOPATH:        c.GOPATH,
		CgoEnabled:    c.CgoEnabled,
		UseAllFiles:   c.UseAllFiles,
		Compiler:      c.Compiler,
		BuildTags:     c.BuildTags,
		ToolTags:      c.ToolTags,
		ReleaseTags:   c.ReleaseTags,
		InstallSuffix: c.InstallSuffix,
	}

		cfg.BuildContext.Compiler: true,
	}
	if cfg.BuildContext.CgoEnabled {
		tags["cgo"] = true
	}
	for _, tag := range cfg.BuildContext.BuildTags {
		tags[tag] = true
	}
	for _, tag := range cfg.BuildContext.ToolTags {
		tags[tag] = true
	}
	for _, tag := range cfg.BuildContext.ReleaseTags {
		tags[tag] = true
	}
	return tags
}

var (
	anyTags     map[string]bool
	anyTagsOnce sync.Once
)

	// Add build tags based on the experiments in effect.
	exps := Experiment.Enabled()
	expTags := make([]string, 0, len(exps)+len(BuildContext.ToolTags))
	for _, exp := range exps {
		expTags = append(expTags, "goexperiment."+exp)
	}
	BuildContext.ToolTags = append(expTags, BuildContext.ToolTags...)
}

// An EnvVar is an environment variable Name=Value.
type EnvVar struct {
	Name    string
	Value   string

	GOAMD64   = goamd64()
	GOARM     = goarm()
	GOARM64   = goarm64()
	GOMIPS    = gomips()
	GOMIPS64  = gomips64()
	GOPPC64   = goppc64()
	GORISCV64 = goriscv64()
	GOWASM    = gowasm()
	ToolTags  = toolTags()
	GO_LDSO   = defaultGO_LDSO
	Version   = version
)

// Error is one of the errors found (if any) in the build configuration.
var Error error

	if goroot := runtime.GOROOT(); goroot != "" {
		c.GOROOT = filepath.Clean(goroot)
	}
	c.GOPATH = envOr("GOPATH", defaultGOPATH())
	c.Compiler = runtime.Compiler
	c.ToolTags = append(c.ToolTags, buildcfg.ToolTags...)

	defaultToolTags = append([]string{}, c.ToolTags...) // our own private copy

	// Each major Go release in the Go 1.x series adds a new
	// "go1.x" release tag. That is, the go1.x tag is present in

	// defaults to empty, but it is usually an error to customize ToolTags or ReleaseTags.
	// ToolTags defaults to build tags appropriate to the current Go toolchain configuration.
	// ReleaseTags defaults to the list of Go releases the current release is compatible with.
	// BuildTags is not set for the Default build Context.
	// In addition to the BuildTags, ToolTags, and ReleaseTags, build constraints

	forcedLdflags = append(forcedLdflags, modeFlag)

	if cfg.BuildContext.InstallSuffix != "" {
		cfg.BuildContext.InstallSuffix += "_"
	}
	cfg.BuildContext.InstallSuffix += mode
	cfg.BuildContext.ToolTags = append(cfg.BuildContext.ToolTags, mode)
}

func buildModeInit() {
	gccgo := cfg.BuildToolchainName == "gccgo"
	var codegenArg string

	// Configure the build mode first, then verify that it is supported.

	if runtime.GOARCH != "amd64" {
		t.Skip("amd64-only test")
	}
	if runtime.GOOS != "linux" && runtime.GOOS != "darwin" {
		t.Skip("test only works on elf or macho platforms")
	}
	for _, tag := range build.Default.ToolTags {
		if tag == "amd64.v2" {
			t.Skip("compiling for GOAMD64=v2 or higher")
		}
	}
	if os.Getenv("TESTGOAMD64V1") != "" {
		t.Skip("recursive call")
	}

pkg debug/elf, const SHT_MIPS_ABIFLAGS = 1879048234
pkg debug/elf, const SHT_MIPS_ABIFLAGS SectionType
pkg encoding/csv, method (*Reader) FieldPos(int) (int, int)
pkg go/build, type Context struct, ToolTags []string
pkg go/parser, const SkipObjectResolution = 64
pkg go/parser, const SkipObjectResolution Mode
pkg image, method (*Alpha) RGBA64At(int, int) color.RGBA64
pkg image, method (*Alpha) SetRGBA64(int, int, color.RGBA64)